Apparatus and method for producing a sealed single-dose break-open package

ABSTRACT

A production method of a sealed single-dose break-open package; wherein the package comprises: a first sheet of semi-rigid plastic; a second sheet of flexible plastic superposed on and sealed to the first sheet to define a sealed pocket that contains a dose of a product; and a weakened zone made in a central zone of the first sheet for guiding, after bending of the package, controlled breaking of the first sheet at the weakened zone to cause formation of an outlet opening for the product through the first sheet; the method includes making in a surface ( 8, 10 ) of the first sheet an incision that constitutes the weakened zone; wherein the incision is made through plastic deformation of the material using an incision tool having a tip that is not sharp, that is, that has a round shape for deforming rather than cutting.

TECHNICAL FIELD

The present invention relates to an apparatus and to a production method for producing a sealed single-dose break-open package.

BACKGROUND ART

The patent application WO2008038074A2 describes a sealed single-dose break-open package; the sealed package comprises a sheet of semi-rigid plastic material and a sheet of flexible plastic material which is superposed on and sealed to the sheet of semi-rigid plastic material to form a sealed pocket that contains a dose of a fluid product. The sheet of semi-rigid plastic material has in the central part a weakened zone for guiding controlled breakage of the sheet of semi-rigid plastic material in such a way as to cause the formation of an outlet opening for the product through the sheet of semi-rigid plastic material itself. In other words, to open the sealed package a user must grab the sealed package itself with the fingers of one hand and “V”-bend the sealed package until the sheet of semi-rigid plastic material breaks at the weakened zone. The weakened zone comprises an inner incision that is made through an inner surface (that is, facing the pocket) of the sheet of semi-rigid plastic material and an outer incision that is made through an outer surface of the sheet of semi-rigid plastic material and aligned with the inner incision.

In patent application WO2008038074A2, the incisions vary in depth in order to break the sheet of semi-rigid plastic material progressively during the “V”-bending of the sealed package. However, making incisions that vary in depth is relatively complicated since it requires a very high precision of movement of the blades of the incision unit; amongst others, the precision of movement of the blades of the incision unit tends to decrease with the increase of the operating speed and as a result, to obtain a very high precision of movement of the blades of the incision unit it is not possible to reach particularly high operating speeds.

Moreover, the sealed single-dose package described in patent application WO2008038074A2 does not allow to apply (spread) the product contained inside the package itself in a precise and intuitive manner on a surface and therefore that package is not suitable to contain spreadable products (that is, to be spread on a surface).

To make the package, patent application WO2008038074A2 describes the use of an apparatus including a reel for feeding a strip of semi-rigid material and a reel for feeding a strip of flexible material, an incision unit and a package forming station including a device for feeding the fluid product and a sealing device. The incision unit has two parallel, facing plates, movable towards each other to grip the strip of semi-rigid material, that support some blades. Each plate is pushed towards the other respectively by a linear actuator in order to hold the strip of semi-rigid material and make an incision on each side of the same.

According to an alternative method described in patent application WO2009040629A2, a “V”-shaped incision that varies in depth is made on each side of the strip of semi-rigid plastic material, with a sharper blade on the side of the strip intended for the outer part of the package. The blades are pushed one against the other in order to hold the strip of semi-rigid material and make the incisions on the same. Even through this method, moving the blades turns out to be difficult and it is not possible to control the depth of the incision.

DISCLOSURE OF THE INVENTION

The object of the present invention is to provide an apparatus and a method for producing a sealed single-dose break-open package that are free from the above mentioned disadvantages.

According to the present invention, an apparatus and a method for producing a sealed single-dose break-open package are provided in accordance with the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be now described with reference to the accompanying drawings that show some non-limiting embodiments of the invention itself, wherein:

FIG. 1 illustrates a topside view in perspective of a sealed single-dose break-open package produced in accordance with the present invention and in a flat configuration;

FIG. 2 illustrates an underside view in perspective of the sealed package of FIG. 1 in a flat configuration;

FIG. 3 is a bottom-up view in perspective of the sealed package of FIG. 1 in a “V”-shaped configuration;

FIG. 4 is a schematic view in cross-section and at a weakened zone of a semi-rigid sheet of the sealed package of FIG. 1;

FIG. 5 is a bottom-up view of the package of FIG. 1;

FIGS. 6-9 are bottom-up views of variations of FIG. 1 package; and

FIG. 10 is a schematic view in cross-section that illustrates the creation of a weakened zone of a semi-rigid sheet of FIG. 1 sealed package;

FIG. 11 is a schematic view in cross-section that illustrates the creation of a weakened zone of a semi-rigid sheet of FIG. 1 sealed package in an alternative embodiment;

FIG. 12 illustrates an apparatus for the production of a sealed single-dose break-open package in a embodiment of the present invention;

FIG. 13 illustrates the incision unit and the sealing and filling unit of the apparatus of FIG. 12;

FIG. 14 illustrates an incision unit of the apparatus of FIG. 12;

FIG. 15 illustrates a detail of the incision unit of the apparatus of FIG. 12.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION

Number 1 in FIGS. 1 and 2 indicates as a whole a sealed single-dose break-open package. The sealed single-dose package 1 comprises a rectangular sheet 2 of semi-rigid plastic material and a rectangular sheet 3 of flexible plastic material superposed on and sealed to sheet 2 of semi-rigid plastic material to form (between sheets 2 and 3) a sealed pocket 4 containing a dose of a fluid product 5.

The sheet 2 of semi-rigid plastic material may have regular or irregular shape and sheet 3 of flexible plastic material may have regular or irregular shape symmetric to the semi-rigid plastic material.

The sheet 2 of semi-rigid plastic material has a weakened zone 6 in the central part for guiding controlled breakage of the sheet 2 of semi-rigid plastic material in such a way as to cause the formation of an outlet opening for the product 5 through the sheet 2 of semi-rigid plastic material. In other words, to open the sealed single-dose package 1, a user has to grip the sealed single-dose package 1 with the fingers of one hand and “V”-bend (as shown in FIG. 3) the sealed single-dose package 1 until the sheet 2 of semi-rigid plastic material breaks at the weakened zone 6. By breaking the sheet 2 of semi-rigid plastic material at the weakened zone 6, the product 5 can flow smoothly and hygienically out of the sealed single-dose package 1.

According to FIG. 4, the weakened zone 6 comprises one inner incision 7 (not passing through, i.e. it does not go completely through the sheet 2 of semi-rigid plastic material) which is made through an inner surface 8 (that is, oriented towards pocket 4 or facing pocket 4) of the sheet 2 of semi-rigid plastic material and a outer incision 9 (not passing through, i.e. it does not go completely through the sheet 2 of semi-rigid plastic material) that is made through an outer surface 10 (that is, opposite to pocket 4) of the sheet 2 of semi-rigid plastic material. The two incisions 7 and 9 are identical (that is, shape and dimensions of the inner incision 7 are equal to the shape and dimensions of the outer incision 9), aligned and superposed (that is, the two incisions 7 and 9 are placed exactly in the same position on the opposite surfaces 8 and 10 of the sheet 2 of semi-rigid plastic material). The two incisions 7 and 9 do not touch, that is, a residual portion of the sheet 2 of semi-rigid plastic material interposes itself between the two incisions 7 and 9, to preserve the integrity of sealed pocket 4. Moreover, the sheet 2 of semi-rigid plastic material and the sheet 3 of flexible plastic material in this example of embodiment are made in such a way that incisions 7 and 9 determine the required breakage of the sheet 2 of semi-rigid plastic material when exposed to the forces generated by the “V”-bending (shown in FIG. 3).

According to the example of embodiment illustrated in FIG. 3, the sheet 2 of semi-rigid plastic material is a laminate and includes an outer supporting layer 11 (that is, on the side opposite to pocket 4 in the area of the outer surface 10) and an inner supporting layer 12 (that is, on the side of pocket 4 in the area of the inner surface 8). An insulating or barrier layer 13 is provided between the two supporting layer 11 and 12 to ensure impermeability to air and/or light; in other words, the barrier layer 13 is enclosed by the two supporting layers 11 and 12 and separates the supporting layers 11 and 12 itself from one another. The supporting layer 12 is covered by a heat-sealable layer 14 which is placed internally (that is, on the same side of pocket 4 and in contact with sheet 3 of flexible plastic material to allow the heat-sealing to the sheet 3 of flexible plastic material itself).

According to some embodiments shown in the attached figures, the two supporting layers 11 and 12 may have the same thickness (i.e. are specular or twins); however, according to other embodiments, the two supporting layers 11 and 12 may have different thicknesses, i.e. the thickness of supporting layer 11 is different from thickness of supporting layer 12.

As non-limiting example, the sheet 2 of semi-rigid plastic material may be composed of: a supporting layer 11 of white polystyrene (PS) with a thickness of 200 micron(±10%), a barrier layer 13 of “Evoh” or dialuminum with a thickness of 10 micron(±10%), a supporting layer 12 of white polystyrene (PS) with a thickness of 200 micron(±10%), and a heat-sealable layer 14 of polyethylene (PE) with a thickness of 50 micron(±10%). Alternatively, supporting layers 11 and 12 may be composed of polylactic acid (PLA) preferably biaxially oriented, and/or the heat-sealable layer 14 may be composed of polypropylene (PP). Polylactic acid (PLA) is generally heat-sealable, therefore when supporting layers 11 and 12 are made of polylactic acid (PLA), heat-sealable layer 14 may be absent since the sheet 3 of flexible plastic material may be heat-sealed directly to supporting layer 12 of polylactic acid (PLA). Moreover, when supporting layers 11 and 12 are made of polylactic acid (PLA) or polypropylene (PP), it is possible to reduce the thickness of the supporting layers 11 and 12 itself since polylactic acid (PLA) and polypropylene (PP) allow to obtain sufficiently rigid supporting layers 11 and 12 even with a small thickness. As example, if supporting layers 11 and 12 are made of polystyrene (PS), the overall thickness of supporting layers 11 and 12 has to be higher than 350-380 micron, while if supporting layers 11 and 12 are made of polylactic acid (PLA) or polypropylene (PP) the overall thickness of supporting layers 11 and 12 may reach even 200 micron.

Each incision 7 or 9 has on the surface (i.e. at the surface of the corresponding supporting layer 11 or 12) a width W that may vary according to the plastic material used to make the supporting layers 11 and 12: with white polystyrene (PS) the width W of each incision 7 or 9 may range between 0.5 e 1.5 mm while with biaxially oriented polylactic acid (PLA) or with polypropylene (PP) the width W of each incision 7 or 9 may range between 2 and 4 mm. As a result, the width W of each incision 7 or 9 when using biaxially oriented polylactic acid (PLA) or polypropylene (PP) is higher than the width W of each incision 7 or 9 when using polystyrene (PS). These differences are due to the fact that biaxially oriented polylactic acid (PLA) and polypropylene (PP) become fragile (i.e. easily breakable) when crushed (deformed by compression) as occurs by making incisions 7 and 9 and as a result, it is more convenient to have relatively wide incisions 7 and 9 to obtain in supporting layers 11 and 12 residual parts (i.e. what remains of supporting layers 11 and 12 in the area of incision 7 and 9) with a high fragility that helps the breakage of package 1 when it is “V”-bended (as shown in FIG. 3). According to another embodiment not shown, in the sheet 2 of semi-rigid plastic material, supporting layer 12 is absent (i.e. the barrier layer 13 is directly in contact with heat-sealable layer 14) and supporting layer 11 has a double thickness (i.e. supporting layer 12 is “embedded” in supporting layer 11).

The outer incision 9 is made through the outer surface 10 of the sheet 2 of semi-rigid plastic material and can be made by deforming locally the sheet 2 of semi-rigid plastic material and in particular the supporting layer 11 of the sheet 2 of semi-rigid plastic material; the outer incision 9 ends before the barrier layer 13 and therefore it does not affect the barrier layer 13 itself.

The inner incision 7 is made in the inner surface 8 of the sheet 2 of semi-rigid plastic material and can be executed by deforming locally the sheet 2 of semi-rigid plastic material and in particular the supporting layer 12 of the sheet 2 of semi-rigid plastic material; the inner incision 7 ends before the barrier layer 13 and therefore it does not affect the barrier layer 13 itself.

In the area of the inner incision 7 the heat-sealable layer 14 can be deformed or torn (partially or completely); in any case, at the inner incision 7 there is no sealing of any kind between the sheet 2 of semi-rigid plastic material and the sheet 3 of flexible plastic material and therefore the possible local damage of the heat-sealable layer 14 does not have any consequence.

In a preferred embodiment, the incision 7 is made only on the inner surface 8 of the sheet 2 of semi-rigid plastic material by deforming locally the sheet 2 of semi-rigid plastic material and in particular the supporting layer 12 of the sheet 2 of semi-rigid plastic material; the inner incision 7 ends before the barrier layer 13 and therefore it does not affect the barrier layer 13 itself (FIG. 11).

In some embodiments, the barrier layer 13 may be located between the two supporting layers 11 and 12 to build a barrier for the product inside the sealed pocket 4. In some embodiments, the incisions 7 and 9 may not affect the barrier layer 13. In some embodiments, the barrier layer 13 may be thick and solid enough to allow a partial penetration of incisions 7 and 9 provided that the barrier layer 13 is designed to maintain its barrier function. In some embodiments, the integrity of barrier layer 13 of the sheet 2 of semi-rigid plastic material secures the barrier function and therefore the tightness for the content of the sealed pocket 4 even in the area of the incisions 7 and 9 and therefore the sealed pocket 4 is suitable to contain also perishable products and/or with controlled bacterial load like food, medicines or cosmetics. During the opening by breakage of the sealed single-dose package 1 by “V”-bending the sealed single-dose package 1 (as shown in FIG. 3), it is necessary to break at the weakened area 6 all the supporting layers 11 and 12, barrier layer 13 and heat-sealable layer 14 of the sheet 2 of semi-rigid plastic material.

In some embodiments, inner incision 7 and outer incision 9 may have an essentially constant depth lengthwise (net of the inevitable construction tolerances).

As shown in FIG. 5, each incision 7 and 9 (the two incisions 7 and 9 are identical to and superposed on each other and therefore not distinguishable in FIG. 5) develops along a single line with broken shape (i.e. a single zig-zag line), that is a line composed of an ordered set of consecutive oriented segments (i.e. such that the second end of a segment matches with the first end of the following segment) and not adjacent (i.e. such that a segment and the following segment do not belong to the same straight line). Moreover, each incision 7 and 9 develops along a single line with broken shape (i.e. a single zig-zag line) that is open (i.e. the first end and the last end do not match) and not intertwined (i.e. the sides of the line have no intersection point). According to some embodiments, the segments of the single line with broken shape (i.e. a zig-zag single line) along which incisions 7 and 9 develop are essentially parallel or essentially perpendicular and therefore a segment forms always an essentially right angle with the next segment.

Each incision 7 and 9 has a “U”-shaped central part 15 and two lateral parts 16 that are placed on the opposite sides of the central part 15 and connected to the central part 15 itself. The two lateral parts 16 are constituted of two respective straight line segments that have identical dimension and are aligned with each other (i.e. one lies on the extension of the other). The central part is constituted of a main segment 17 that is essentially parallel to and offset from (i.e. not aligned) the two lateral parts 16 and of two joining segments 18 that are essentially parallel to and offset from each other (i.e. not aligned), are essentially perpendicular to the main segment 17 and are essentially perpendicular to the two lateral parts 16; each joining segment 18 connects a lateral part 16 to one end of the main segment 17.

On the whole, each incision 7 and 9 has a square “Ω” shape (i.e. constituted only of segments essentially parallel or essentially perpendicular to each other).

As better shown in the attached figures, the weakened zone 6 does not affect the whole width of the sheet 2 of semi-rigid plastic material, but affects only a central portion of the sheet 2 of semi-rigid plastic material leaving intact (i.e. without the weakened zone 6) two lateral portions of the sheet 2 of semi-rigid plastic material symmetrically placed on opposite sides of the weakened zone 6 itself.

According to a possible embodiment, the weakened zone 6 (i.e. the two superposed incisions 7 and 9) increases as the density of the product 5 contained in the pocket 4 of the sealed single-dose package 1 increases, that is, the weakened zone 6 (i.e. the two superposed incisions 7 and 9) decreases as the density of the product 5 contained in the pocket 4 of the sealed single-dose package 1 decreases. As a result, the embodiment shown in FIG. 5 can be suitable to products with a higher density such as creams or granular products while the embodiment shown in FIG. 6 can be suitable to products with a lower density like liquids.

According to different embodiments shown in FIGS. 5-9, the main segment 17 can be linear, angled (broken) or curved. Likewise, also lateral parts 16 or joining segments 18 can be linear, angled (broken) or curved.

According to a possible embodiment shown in FIG. 10, the incisions 7 and 9 are made by means of plastic deformation of the material using corresponding incision tools 19, each of them having a tip that is not sharp, that is to say, that has a round shape (namely a rounded tip) for deforming rather than cutting the supporting layers 11 and 12 of the sheet 2 of semi-rigid plastic material.

According to a preferred embodiment shown in FIG. 11, only one incision 7 is made on the inner surface 8 of the sheet 2 of semi-rigid plastic material by deforming locally the sheet 2 of semi-rigid plastic material and in particular the supporting layer 12 of the sheet 2 of semi-rigid plastic material; by means of an incision tool 19 having a tip that is not sharp, that is to say, that has a round shape (namely a rounded tip). In particular, the tip may have different degrees of sharpness and may have any shape according to the product contained in the package.

According to the example of embodiment illustrated in the attached figures, the sealed single-dose package 1 has a rectangular shape; obviously due to aesthetic reasons the sealed single-dose package 1 may be shaped differently: rounded, elliptic, “bottle”-shaped, rhomboidal, pentagonal, hexagonal, triangular, squared, “bone”-shaped.

The sealed single-dose package 1 described above has numerous advantages.

Firstly, the sealed single-dose package 1 described above is easier and cheaper to produce than a similar known package 1 (for example of the type described in patent application WO2008038074A2), since the incisions 7 and 9 have a constant depth and therefore are easier to be made even with high operating speed.

Moreover, the package 1 described above allows to dose in a simple and efficient way all kind of fluid (liquid or creamy), powdered or granular products and it is particularly suitable for spreading the product 5 on a surface thanks to the area of the sheet 2 of semi-rigid plastic material enclosed by the central part 15 of the incisions 7 ad 9 that can be separated (moved) from the rest of sheet 2 of semi-rigid plastic material becoming a spatula useful to spread the product 5 itself. In other words, the central portion on the main segment 17, between joining segments 18 is designed to extend when package 1 is V-bended, in a trajectory beyond the adjacent structures of the sheet 2 of semi-rigid plastic material to work as a scoop for spreading the product that comes out from the opening (as shown in FIG. 3).

In FIG. 12, 20 indicates an apparatus for the production of a sealed single-dose break-open package 1 in a embodiment of the present invention.

The apparatus 20 includes a first feeding unit 21 of a first strip of semi-rigid plastic material, a second feeding unit 22 of a second strip of flexible plastic material, an incision unit 23 to make a deformation in the strip of semi-rigid plastic material and a sealing and filling unit 24 for sealing at least one portion of the strip of semi-rigid material to a corresponding portion of the strip of flexible material to create pocket 4 and for filling pocket 4.

In the illustrated embodiment, the apparatus 20 includes furthermore a printing unit 25 placed between the first feeding unit 21 of the first strip of semi-rigid plastic material and the incision unit 23.

The first feeding unit 21 comprises a reel 211 from which a strip of semi-rigid plastic material is unwound. The reel 211 is preferably driven by a brushless motor. The strip of plastic material has a thickness preferably ranging between 200 micron and 450 micron.

The strip of semi-rigid plastic material goes to the printing unit 25 that includes at least a thermal transfer printer for printing, on the side of the strip that will form the outer surface of the package, a bar code, a batch indication, etc. . . . The printing unit 25 includes advantageously a number of printers 251, 252, 253 installed in-line.

After the printing unit 25, the strip of semi-rigid plastic material moves to the incision unit 23, where, according to the invention, occurs a deformation or shaping of the side of the strip that will form the inner surface of the semi-rigid sheet, on which there is the heat-sealing layer.

According to the invention, as shown in FIGS. 13, 14, the incision unit 23 includes a first plate 231 and a second pate 232 opposed to the first plate 231, wherein the second plate 232 includes at least one incision tool 19, wherein the incision tool 19 is movable from a first position far from the first plate 231 to a contact position with the first plate 231 to obtain a deformation in the strip of semi-rigid material placed between the first plate 231 and the second plate 232. In particular, the incision tool 19 has a tip with different degrees of sharpness and may have any shape.

The surface of the first plate 231 and/or the second plate 232 is preferably ground. The first plate 231 represents a supporting surface for the strip to be deformed.

As shown in detail in FIG. 15, the second plate 232 has at least one micrometer measuring tool 191 placed on the opposite side from the first plate 231, which adjusts the range of the incision tool 19. The tool 191 can be manual or motorized. Preferably, the range of incision tool 19 is adjusted in relation to the second plate 232, and the second plate 232 is movable in relation to the first plate 231, which is fixed.

By means of a linear actuator or a motor, the second supporting plate 232 of the incision tool 19 is moved towards the first plate 231 so that one end of the incision tool 19 moves according to the preset distance towards the first supporting plate 231 to create the deformation in the strip of semi-rigid material. In this way the deformation or shaping is made with constant depth.

The end of the incision tool 19 has advantageously the shape of the incision that has to be made in the sheet of semi-rigid material.

Preferably, the second plate 232 has a number of incision tools 19 positioned in line, each one joined with a corresponding micrometer measuring tool 191, manual or motorized.

The shaping is made advantageously only on the side of the strip that will become the inner surface 8 of the semi-rigid sheet 2.

In this way it is possible to control exactly the range of the incision tool and therefore the deformation depth, so that the semi-rigid sheet is not damaged by cutting. In particular, if this has an inner barrier layer, making the incision by means of the apparatus according to the present invention allows to control that the barrier does not get damaged.

In fact, it is no longer a matter of controlling a blade during the incision to vary the cutting depth along the strip, but of simply adjusting the range of the incision tool 19 so that this creates a deformation with constant depth and with a predetermined shape in the inner surface 8 of the semi-rigid sheet 2.

In the embodiment shown in FIGS. 12, 13 and 14, the strip of semi-rigid material fits between the first plate 231 and the second plate 232 with an essentially vertical bottom-up direction.

During shaping, the strip stops and leans against the first plate 231.

To perform this intermittent operation in an apparatus on continuous cycle, the apparatus 20 includes advantageously a blocking device 26 which determines stop and recovery in relation to the continuous cycle. Preferably, the blocking device 26 allows to change the position of the deformation from the axis of the bag. In the illustrated embodiment, the blocking device 26 comprises a pair of blocking plates 261, 262, one movable and the other fixed, placed upstream of the incision unit 23, in particular below the first plate 231 and the second plate 232 for the shaping, a pair of rubber rollers 263, 264 placed downstream of the incision unit 23, in particular above the first plate 231 and the second plate 232, and an active dancer roller 265 pneumatically or electronically controlled. According to the dimensions set by the user in the software of the apparatus, the dancer roller 265 has a double function, that is, it allows to determine the length of the bag and the position of the incision from the axis of the bag and to perform a mechanical stop without interrupting the continuous cycle of the apparatus.

After the shaping, the strip of semi-rigid material moves to the sealing and filling unit 24, where it is joined to the strip of flexible material coming from a reel 221, preferably driven by a brushless motor, of the second feeding unit 22. The strip of flexible material has a thickness preferably ranging between 62 micron and 100 micron.

The sealing and filling unit 24 includes a vertical sealing device 241, a filling device 246 and an horizontal sealing device 247.

In the sealing and filling unit 24, the bag or the bags is/are heat-sealed, preferably by means of compressed air. Compared to the known devices that use springs, the use of compressed air allows to perform a constant sealing and to reduce maintenance work.

The vertical sealing device 241 has a first pair of rollers including a first rubber roller 242 and a second warm roller 243 both equipped with grooves and a second pair of cold rollers 244, 245, for riveting the sealing made by the previous pair of rollers 242, 243, also equipped with grooves and placed below the first pair of rollers 242, 243 in vertical direction.

The horizontal sealing device 247 has a single rotary sealer, consisting of a pair of rollers including a first rubber roller 248 and a second warm roller 249. The horizontal sealing device 246 closes the filled packages and at the same time, during the rotation, it constitutes the closed base of the packages that have still to be filled.

In sequence, firstly the vertical seals of the package are made, than the package is filled, than it is closed, creating with the same movement the base for the following package.

The apparatus 20 includes a cutting unit placed after the sealing and filling unit 24, wherein each package is separated from the material exceeding from sealing (scrap). The single packages are then positioned on a belt 27, that conveys them to the following step of production. 

1. A production method for producing a sealed single-dose break-open package; the sealed package comprises: a first sheet of semi-rigid plastic material; a second sheet of flexible plastic material superposed on and sealed to the first sheet to define a sealed pocket that contains a dose of a product; and a weakened zone that is made in a central zone of the first sheet for guiding, after bending of the sealed package, controlled breaking of the first sheet at the weakened zone in such a way as to cause the formation of an outlet opening for the product through the first sheet itself; the production method comprises the step of making in a surface of the first sheet at least one incision that constitutes the weakened zone; the production method is characterised in that the incision is made by means of plastic deformation of the material using an incision tool having a tip that is not sharp, that is to say, that has a round shape for deforming rather than cutting.
 2. The production method according to claim 1 and comprising the further step of varying a width of the incision at the surface depending on the plastic material of which the first sheet is composed.
 3. The production method according to claim 1, wherein the incision has constant depth.
 4. The production method according to claim 1, wherein the incision is made on the inner surface facing the pocket of the first sheet of semi-rigid plastic material by deforming locally the first sheet of semi-rigid plastic material.
 5. The production method according to claim 1, wherein the incision tool is movable from a position far from a supporting plate of a strip of semi-rigid material to a position of contact with the supporting plate to perform a shaping of the strip.
 6. The production method according to claim 1, wherein the incision tool has one end with the shape corresponding to the shape of the incision to be made on the surface of the sheet.
 7. An apparatus for the production of a sealed single-dose break-open package, wherein the sealed package comprises: a first sheet of semi-rigid plastic material; a second sheet of flexible plastic material superposed on and sealed to the first sheet to define a sealed pocket that contains a dose of a product; and a weakened zone that is made in a central zone of the first sheet for guiding, after bending of the sealed package, controlled breaking of the first sheet at the weakened zone in such a way as to cause the formation of an outlet opening for the product through the first sheet itself; wherein the apparatus comprises at least a first feeding unit of a first strip of semi-rigid plastic material, at least a second feeding unit of a second strip of flexible plastic material, at least one incision unit to make a deformation in the strip of semi-rigid material, and at least one sealing and filling unit for sealing at least one portion of the strip of semi-rigid material to a corresponding portion of the strip of flexible material to form the pocket and for filling pocket, the apparatus being characterised by the fact that the incision unit comprises a first plate and a second plate opposed to the first, wherein the second plate comprises at least one incision tool, wherein the incision tool is movable from a first position far from the first plate to a predefined position close to the first plate to make a deformation in the strip of semi-rigid material placed between the first plate and the second plate.
 8. The apparatus according to claim 7, wherein the surface of the first plate and/or of the second plate oriented towards the strip of semi-rigid material is ground.
 9. The apparatus according to claim 7, wherein the first plate is fixed and the second plate is movable to bring the incision tool to a predefined distance from the first plate.
 10. The apparatus according to claim 7, wherein it comprises at least one micrometer measuring tool to adjust the range of the incision tool, in particular with reference to the second plate.
 11. The apparatus according to claim 7, wherein it comprises a plurality of incision tools positioned in line and joined with the corresponding micrometers.
 12. The apparatus according to claim 7, wherein it comprises a blocking device that has a pair of blocking plates placed upstream of the incision unit, a pair of rubber rollers placed downstream of the incision unit, and an active dancer roller pneumatically or electronically controlled. 